Born in Toulouse, France, the sons of modest merchants, he and his brother, Pierre, rose from obscurity to become two of the wealthiest merchants of France. By way of lending money to the government, Antoine was ennobled as the marquis du Châtel, a title he transmitted to his elder son Louis-François. He became a financial counselor to Louis XIV. He invested in the Guinea Company and the Asiento Company, two lucrative overseas franchises. The king eventually offered him a 15‑year trademonopoly in Louisiana.